1. Field of the Invention
This invention relates generally to devices for charging an electric battery of a motorized vehicle, and more particularly to devices for harnessing wind energy to charge an electric battery of an electric car.
2. Background Art
As used here, the term “electric car,” “hybrid electric,” “hybrid gas/electric,” “all electric motor,” and “all-electric vehicle” and “hybrid motor vehicle” refers to any motor vehicle that is powered substantially, in-part, and/or exclusively by an electric drive train. Hybrid motor vehicles with a drive train powered by an internal combustion engine in combination with one or more electric motors are now common on our streets and highways, but public acceptance of all-electric vehicles has been relatively slow. The slow acceptance of all-electric vehicles is largely due to the limited driving range such vehicles are currently capable of on a single charge of their electric storage batteries.
In addition, currently, there are relatively few places accessible to the public for recharging the batteries of an all-electric vehicle compared to the number of gasoline and diesel refueling stations. Further, the time required to recharge the batteries is significantly longer than the time required to fill the fuel tank of a vehicle that runs on gasoline or diesel fuel. Driving an all-electric vehicle beyond its rated driving range and to a location that lacks suitable battery charging facilities would likely mean incurring the time and expense for tow truck assistance before the driver could be underway again.
To address these challenges for electric and hybrid motor vehicles, and to promote public acceptance of battery-powered hybrid and all-electric cars and vehicles, it would be desirable to harness wind energy to help maintain some of the charge in the electric storage battery of all types of vehicles having one or more batteries, including for example hybrid gas/electric vehicles, electric cars, and all-electric vehicles, while the vehicle is being driven, as well as to charge the battery by harnessing wind energy while the vehicle is parked.
U.S. Pat. No. 7,886,669 B2 discloses a method for harnessing wind energy to charge a system battery that powered a limited number of electronic components of a stationary locomotive after engine shut down or while the locomotive coasts under gravity with its engine shut down. Those components can include lights and on-board monitoring and display systems of the locomotive.
This method also describes an electric device, such as a motor that could be run in an electrical generator mode. The motor can be coupled to an airflow device rotatable by ambient air flow. A controller is also included to activate the airflow device and generator when some minimum rotational speed of the airflow device occurs. For instance, the airflow device can be fan blades driven by the electric device to provide cooling. The airflow device can also harness ambient wind energy to drive the electric device to generate electricity for the electronic components or battery charging.
U.S. Pat. No. 7,828,091 B2 discloses an all electric vehicle having an internal wind turbine generator mounted in the nose of the vehicle. The generator uses compressed air and a high voltage battery to generate electricity to power the DC motors that drove the vehicle. When available wind energy was inadequate, compressed air stored in one or more air tanks is required to drive an air motor coupled to an electric generator to generate electricity, which recharges the electric battery and/or powers the DC motors.
The devices known in this technical field have been limited for use to specialized electric vehicle applications, and have not been able to efficiently harvest wind energy for use with more commonly available electric vehicles, such as electric automobiles. For example, the device used with locomotives employs wind devices that are not suitable for use with electric automobiles because of the need to be integrated into existing blowers, or which must protrude outside the locomotive.
The wind turbine generator variant is designed to be mounted about a front end of what appears to be the electric motor of an automobile, and is not suited for efficient harvesting of wind energy passing around the vehicle. Either of these types of systems require a high level of technical expertise and knowledge of the host vehicle to incorporate, maintain, repair, and/or upgrade the electricity generation capability.
New methods and devices are needed to more efficiently harvest energy from an airstream to generate electricity for use with electric vehicles. Also needed are devices that are less complex, and which are not limited to use in specialized applications. What is needed are devices that can be adapted for use with a wider range of electric vehicles, especially consumer automotive vehicles. It would also be advantageous if wind energy harvesting methods and systems were available that are usable by users who may not have very advanced technical training and knowledge of how to install, maintain, and operate such methods and devices.